1. Field of the Invention
Embodiments of the present invention generally relate to data protection and recovery systems and, more particularly, to a method and apparatus for maintaining an amount of reserve space using virtual placeholders.
2. Description of the Related Art
Normally, database applications (e.g., MICROSOFT Exchange Server) create log files to track operations performed on database files. The log files are used to recover the database files upon an occurrence of a data loss event (e.g., a database files are corrupted, a server fails and the like). For example, the Exchange Server creates log files every time a message activity is conducted by a user (e.g., a message is created, sent, deleted, received and the like). Exchange Server stores the log files and the database files in log volumes and database volumes, respectively.
System administrators are tasked with the duty to maintain and secure computer systems. For example, the system administrators are responsible for configuring storage resources and processes related to the Exchange Server in conformity with established best practices and guidelines. Such best practices and guidelines may provide examples for estimating a size of storage space for a log volume in various backup scenarios. For example, incremental backup images accumulate a large number of log files. These log files must be maintained to facilitate restoration of the backup. Occasionally, the system administrators underestimate the size of the storage space needed for the files, which disrupts the restoration and/or recovery processes. System administrators need to ensure there is always enough space for the restoration and/or recovery processes to continue. For example, the recovery process cannot begin until the restoration process is completed.
The recovery process associated with the Exchange Server replays the database using the log files and the database files. Most of the time, the log files need to be restored from a storage device (e.g., a tape drive, a disk drive and the like) before they are applied to the database files. The log files are restored to the log volume and quickly fill up the storage space allocated to the log volume. When there is not enough storage space for the restoration and/or recovery processes to continue, the database is not recovered causing a loss of productivity and an increase in expenses.
Therefore, there is a need in the art for a method and apparatus for maintaining an amount of reserve space using virtual placeholders during database recovery.